Xuan Thuy

Xuan Thuy National Park protects 7,100 hectares of coastal wetlands, mangroves, and intertidal habitats at the mouth of the Red River in Nam Dinh Province, northern Vietnam. Established in 2003, it was Vietnam's first Ramsar Wetland of International Importance, designated in 1989 before the national park was established. The park encompasses the Cuoi Hai Island and surrounding mudflats and mangrove forests of the Bai Vang estuary. Xuan Thuy is one of the most important sites on the East Asian-Australasian Flyway and a critical wintering ground for migratory shorebirds traveling from Arctic Russia and Alaska to Southeast Asia and Australia.

Xuan Thuy is internationally recognized as a shorebird sanctuary. During the northern winter (September–March), tens of thousands of migratory shorebirds use the intertidal mudflats as a feeding ground, including globally threatened species such as the spoon-billed sandpiper, the great knot, the bar-tailed godwit, and the red knot. The spoon-billed sandpiper—with a global population estimated at only a few hundred individuals—uses Xuan Thuy as a critical stopover and wintering site. Large numbers of ducks, geese, and herons winter in the reserve. The mangroves support breeding colonies of herons, egrets, and cormorants.

The park's mangrove forest is dominated by Kandelia obovata and Aegiceras corniculatum, with contributions from various Avicennia and Rhizophora species. The mangroves provide essential fish nursery habitat and protect the coast from erosion and storm surge. Seagrass beds (Halophila ovalis) in the shallow subtidal zone support waterbird foraging and are a food source for the endangered dugong, which occasionally enters the estuary. Pioneer vegetation on newly accreted mudflats includes cordgrass (Spartina) in some areas, and natural mangrove colonization is actively expanding the forest.

Xuan Thuy is located at the mouth of the Day River (a distributary of the Red River), where sediment deposited by the Red River system creates the intertidal mudflats that are the park's primary habitat. The Red River carries enormous quantities of sediment from its Yunnan (China) headwaters, and the delta is actively prograding—the coastline has advanced significantly over historical times. The mudflat sediments are very fine silt and clay, providing rich benthic invertebrate communities. The delta coast is low-lying and highly vulnerable to sea level rise and typhoon-driven storm surge.

Nam Dinh Province experiences a subtropical monsoon climate with a distinct seasonal pattern. The wet season (May–September) brings hot, humid conditions and significant rainfall (1,700–1,900 mm annually). Winters (November–March) are cool and dry (10–20°C), coinciding with the peak arrival of migratory shorebirds. Typhoons affect the coast from June through November, and the low-lying delta is particularly vulnerable to surge flooding. The cool winter temperatures create ideal conditions for the Arctic-breeding shorebirds that winter here. Sea surface temperatures in the Gulf of Tonkin range from 20–30°C seasonally.

The Red River Delta has been the heartland of Vietnamese civilization for over 2,000 years, and the coastal zones have been used intensively for rice farming, salt production, and fishing since ancient times. The Cuoi Hai Island area was historically important for salt production. The mangroves were heavily exploited for timber, charcoal, and tannin. During the Vietnam War, the Red River Delta coast was heavily bombed and mined. After reunification, coastal development—including large-scale shrimp aquaculture—converted much of the remaining coastal wetland. The Xuan Thuy area retains significance as a rare coastal refuge.

The Xuan Thuy wetland was recognized internationally when it became Vietnam's first Ramsar site in 1989, during a period when Vietnam was still closed to most international visitors. The Ramsar designation preceded the formal nature reserve designation and was instrumental in mobilizing international conservation attention. The area was formally protected as a nature reserve in the 1990s and upgraded to national park in 2003. BirdLife International has maintained a long-term partnership with park management for shorebird monitoring, establishing one of Vietnam's most rigorous annual waterbird count programs.

The primary attraction is shorebird watching—guided boat tours on the tidal channels provide access to the mudflat feeding areas, where thousands of shorebirds can be observed at close range. The mangrove forest boat tours offer a different experience, with herons, kingfishers, and fishing communities visible along the waterways. Overnight stays at community guesthouses allow early morning access to the mudflats at optimal tidal times for bird watching. Cultural visits to fishing communities in the park buffer zone demonstrate traditional fishing methods.

The park headquarters is located at Giao Thien commune, Giao Thuy district, Nam Dinh Province. The nearest city is Nam Dinh city (50 km), which is 2 hours from Hanoi by bus or train. Local buses and motorbikes provide the final access to the park. Boat tours can be arranged at the park headquarters or through guesthouses in Giao Thien commune. Community homestays provide accommodation at the park boundary. The best time to visit is October–March for shorebird watching. Advance booking is recommended for guided tours during peak migration periods.

The spoon-billed sandpiper's critical use of Xuan Thuy has made the park a focal point of international conservation effort—the Wildfowl and Wetlands Trust (WWT), BirdLife International, and Vietnamese partners maintain an intensive conservation program including captive breeding, habitat management, and local community engagement. Aquaculture expansion continues to convert coastal habitat. Plastic pollution and fishing waste degrade water quality and can entangle birds. Climate change and sea level rise threaten the low-lying intertidal habitat. Continued community engagement with local fishers—who are both stakeholders and important conservation allies—is essential.